Rockwell hardness, 100 coils produced in sequence at a Chicago Steel Mill
#ROCKWELL HARDNESS (MEASURED ON ROCKWELL "B" SCALE) OF A SAMPLE OF 100 STEEL
#COILS PRODUCED IN SEQUENCE IN A CHICAGO STEEL MILL.
64.
63.
57.
63.
57.
58.
65.
74.
61.
50.
60.
58.
64.
59.
55.
64.
54.
53.
60.
57.
63.
63.
60.
62.
61.
56.
63.
65.
60.
62.
64.
58.
63.
53.
63.
53.
60.
61.
58.
57.
55.
54.
58.
58.
58.
59.
55.
55.
62.
54.
55.
65.
67.
66.
59.
55.
50.
54.
57.
58.
61.
62.
66.
63.
63.
58.
59.
60.
63.
64.
60.
62.
58.
60.
60.
64.
58.
59.
58.
60.
62.
56.
52.
63.
57.
59.
57.
63.
59.
63.
60.
54.
55.
55.
53.
62.
62.
62.
50.
58.

